Is the cost breakdown for a single-family house plausible?

400 €/m² is now completely normal in many parts of the country.

Let's be honest, this isn't a competition for the lowest price but rather a realistic assessment of the civil engineering costs.

You can also tell him what the rest cost that isn't listed there and what it costs if you have it done. Not everyone wants or can contribute any own work here.

Honestly?...this is the price if you have it "done"...this is the price I paid the company for the work performed..."0" own contribution did I make in this area...I rather doubt the people who say you have to budget 20,000€ and up for earthworks.

Maybe I have a different understanding of earthworks, for us it included the following:

I paid extra for the removal of a part of the soil - it was €19.55 per m³ of soil.

Maybe.

I can only report from my perspective. The financing was set up 9 months ago. Steel has increased by 10%, windows have become 2k€ more expensive, a geothermal heat exchanger has been added, landfill costs have increased by 10%, etc.

So far, I haven’t found any position where I can say that anything offsets the price increase.

A kind of mixed calculation is probably also when there’s no longer enough money left for the outdoor area

Now really, but that also confirms my opinion. Windows costing 2k more hardly means a 20% price increase.
Geothermal heat exchanger probably means customized...
Landfilling, okay, but not 2k.
You apparently have a high standard.

I will never really be able to understand your experiences. Certain price increases can’t be avoided, but it doesn’t amount to 10-20k. If I spontaneously decide on the masonry chimney, then I also shouldn’t be surprised. Recently I read that the material costs for the entrance podium alone were 2,500€ (and exactly this was generalized), then 1,800€/sqm will not be enough...

It often seems to me here as if nobody has a contact or a known craftsman who writes a fair invoice. Maybe I’m the only one who had that privilege...

Let's stick to the known facts. Land in a residential area near Berlin 400,- Since we know that around Berlin it is flat and sandy, Märkische Heide, Märkischer Sand, no nasty surprises are to be expected. So he gets a foundation for 15 including sewage and rainwater pipe. That should work. Everything about the kitchen and such has been said, the OP obviously doesn't want to install Klausbärbel. 20 for a garden on flat terrain is totally fine. For 7.5 you can easily get the materials for painting and floors outside the tiles. Only, I hope the skills are enough for d.i.y. Or the OP knows someone who does it cash on the barrelhead, we don't want to go into that further. So, yes build.

I’ve just had a look: and the OP both come from Brandenburg, where building is even cheaper than in SH or Lower Saxony. At least that’s what I’ve often read here in the forum. Someone noticed a few days ago that this might also be due to the proximity to Poland. I can well imagine that if the labor force comes from neighboring countries, the price is also lower. At least that was the case with us. In that respect, these prices could be accurate. But still, it really can’t be that there’s constantly a competition here about who paid the lowest price. Take the bathroom washbasin as an example: I believe I remember that prices from €1000 were quoted at the hardware store. In the sanitary showroom from €2000. Poco and Ikea about €500. To me, it was all too expensive and I already had a wooden board painted with boat varnish in the old house, into which a built-in washbasin was installed. So now our countertop washbasin got a 1.60 m long kitchen worktop. The supports were €60 from Praktiker. Below that an Ikea base cabinet. I think we were at about €150 total. But that’s not a reason for me to say that a washbasin costs €150 here. It cost me that because we wanted a creative solution. Still, the price, when someone asks here, is around €1000 upwards. I wouldn’t take Poco and Ikea as an average value in the calculation either. Basically, the average standard should be stated and not the creative alternative, just as little as the Mercedes/Miele price. Apart from that, no one benefits here from not giving real prices. If someone doesn’t have to pay for the disposal of their excavation, that’s great for them. But it could be that the current builder is less lucky and has to pay heavily in the four-digit range: that really hurts when the buffer you had has already flowed into the reinforced foundation slab. Then the mixed calculation for the carport has to cover the extras in the kitchen and sanitary, and you have to save for the carport over years. And the phrase like “if there’s still money left, then...” echoes its mocking song in the empty rooms of the new building.